Tubular header and method of making the same



Sept. 5, 1933. J, PRENTlCE 1,925,847

"TUBULAR READER Arm uETHoD or MAKING THE SAME Fgiled Oct. 23, 1929 2 Sheets-Sheet 2 Fig-.5. Fig-.4 /1 712271/ 21d l VEN R- ATTORNEYS.

Patented Sept. 5, 1933 UNITED STATES PATENT OFFICE 'mama naam-:n AND Ma'rnon or Manned m snm John Prentice, Bayonne, N. J., assignor to The Babcock Wilcox Company, Bayonne, N. I.,

This invention relates to a novel and` imDrOved form of header, particularly adapted for high pressure work, and to a novel and improved method of forming such a header.

I'he invention will be best understood from the following description and the annexed drawings.

in which I have shown a selected ement of header constructed according to my invention and in which I have indicated one example of my improved method. In the drawingsz Fig. 1 is a vertical view, partly in section and partly in elevation, through a boiler and associated furnace showing headers constructed ac coxding to the invention; A Fig. 2 1s e secties on the line 2 2 o: Fig. 1; Fig. 8 is a longitudinal sectional view through one end of a header indicating the first step in my method;

Fig.4isaviewsimilartoFig.3andshowing v the second step in the method; Fig. 5 is a view indicating the next step in the practice of my method, showing one form of apparatus which may be employed in practicing this step:

26 Figs. 6 and 'I are fragmentary views showing the .relation of the tools, indicated in Fig. 5, to the work at different points in the method of forming the header;

Fig. 8 is a longitudinal View, partly in elevation and partly in section, showing the completed header; and

Fig. 9 is a view taken from the right of Fig. 8 and showing the right-hand end of the header.

Referring first to Fig. 1. I have shown therein a boiler of a type in which my novel form of header may be employed to advantage. In this figure is shown a furnace having a combustion chamber 1, above which are disposed the boiler tubes 2 and s, the tubes 3 being connected et' opposite ends to headers 4 which are preferably lconstructed according to this invention. The headers are connected at their upper ends to a steam and water drum 5 by means of nipples-6 and '1, these nipples being substantially centrally t5 disposed with respect to the headers. At their lower ends the headers are connected by curved nipples 8 and 9 to transversely extending drums l0 and 1l, and it is to be noted that these nipples 6 and 9 enter the headers 4 eccentricaliy to said headers. 'I'he drums l0 and i1 are connected together by the tubes 2 and between the tubes 2 and 3 are disposed superheated tubes 12. Suitable firing apparatus, indicated as burners i3, may be employed.

'IheA headers are preferably formed as seamless forged tubes in order to better withstand the 'high pressures for which this type of boiler is designed.y I will now describe a selected example of the method by which these headers may be formed. 'U0

Referring first to Fig. 3, I have shown therein one end of a seamless tube 14 and the first step in my process preferably comprises cutting the end of this tube, as indicated at 15, at an angle to its axis other than a right angle. The next 05 step is to swedge out a bump 16 on one side of the tube, preferably on the side which is rendered shorter than the other by the first step of cutting obliqueiy, as indicated in Fig. 3. This bump may be formed by any well-known means for forcing out the metal of the tube. The next step is preferably to form a flange surrounding the deformed end of the tube. This may be conveniently done by the apparatus shown in Fig. 5, which comprises a support 17 for the tube and a rotary 75 wheel 18 having a threaded member 19 upon which is adjustably mounted a block 20 carrying rolls 21 and 22. The next step may also be practiced by this same apparatus, this step consisting in forcing inwardly the flange to the approximate position shown in Fig. 6. This may conveniently be done by means of the roll 21, acting upon the tube outside of the nange 23 which has previously been formed by the roll in the preceding step. After the parts have reached some such position as indicated in Fig. 6, the spinning'operation of the roll 21 may be continued until the flange 23 is brought completely together, as indicated by dotted lines in Fig. 8, thus forming what is commonly called a rose, It will be seen that this rose is disposed eccentrically to the center of the tube. The roll 22 may then be used as indicated in Fig. 'l to flatten out the tube end at the rose and form a flattened end portion with the rose substantially at its center. This flattened portion extends from the approximate center of the tube or header end, this center being indicated at 24 in Fig. 8. to the edge of the fold at 25, this fold being formed at the flanged swedged portion or bump 16. A hole 26 can then be cut in this flattened portion and it will be seen that this hole will remove the relatively weak metal at and surrounding the rose. In this way an eccentrically disposed hole may be formed at one end of a tubular header without weakening the header, as would be the case if the tube were closed at a point approximately at its center and then the hole were formed eccentrically. The weaker metal is adjacent the point where the un closure is formed and by this invention this weaker metal is eccentrically of the tube at the approximate place where the hole is to be metal is cut out to form ple 8, for example, may be connected to the header at right angles to the header surface in a situation such as is shown in Fig. 1, in which the nipple approaches the header end at an angle'to its axis.

. Referring to Fig. 8, the opposite end 28 of the header may be closed by the same method as described labove and then a hole 29 may be cut therein for entry of a nipple, such as the nipple 6, for example. To close this end 28, the rolls 21 and 22 may be used insuccession and then a third roll ofv a still flatter yangle may be employed to finish the closure.l For example, the rolls 21 and 22 are 45 and 35 rolls, respectively, and these two used in succession on the right-hand end of the header are usually suilicient to do the Work.l In closing the left-hand end, Vthe work may be conveniently finished with a 10 roll. The forming or spinning operation is preferably done at a temperature of approximately 1900 to 2000 F.

1. The method of manufacturing a tubular header which comprises forming an eccentric opening in one end of a tube and closing said end by forcing in the metal from the periphery of the opening toward the center of said eccentric opening, flattening the end around said 'center of the eccentric opening, and cutting out the metal in said flattened portion to form a hole adapted to receive a nipple.

2. The method of manufacturing a cylindrical tubular header which comprises cutting the end of a tube at an angle to its axis other than a right angle, forcing outwardly a portion of the tube wall to form a non-circular opening at the end, shaping the metal at the end to form a closure having a at portion on the side of the tube adjacent said forced out portion, and cutting a hole in the metal of said flattened portion to form a'hole adapted to receive a nipple. y

3. The method of manufacturing a tubular header which comprises cutting a tube atV an angle to its axis other than a right angle, forming the end of said tube with an eccentric opening, closing the end of said tube by forcing the metal from the periphery of the opening toward a point disposed eccentrically to the tube. and

forming an eccentric tube seat by removing a section of the metal located at said point.

4. The method of manufacturing a tubular header which comprises forming an eccentric opening in one end of a tube, closing said end by forcing in the metal from the periphery of the opening toward the center of said eccentric opening, and removing a section of th'e forced in metal at said point to form an eccentric tube seat.

5. The method of making a high pressure header with a tube opening therein eccentrically tened portion away to form a tube opening including said point of last closure.

V6. The methodv of making a cylindrical high pressure header with a tubeopening therein eccentrically arranged relative to the `axis thereof from a tubular blank of uniform circular crosssection, which comprises spinning one end of said blank inwardly to form a substantially convex end wall, forging said end wall to form a flattened portion at anoblique angle to and at one side of the axisof the blank and including the point of last closure formed in said spinning operation, and cutting the part of said flattened portion including said point of last closure away to form. a circular tube opening having its axis intersecting the axis of said body portion.

7*. The method ofA making a high pressure header with a tube opening -in. an end wall thereof eccentrically arranged relative to the axis'of the header from a tubular blank, which' comprises cutting the tubularblank at an oblique, angle to its axis, forming a bulge in the cut end of the shorter side wall, substantially closing the out end of the blank by spinning operationseffecting a positioning of the point of last closure offset from the axis of the blank, flattening a portion of the convex end wall so formed which includes the point of last closure, and, removing metal from said flattened portion to form a tube closure.

lopening therein including -the 'point of last 115 8'. As an article of manufacture, a forged steam A tion extending at an oblique angle to the axis,120

of said body portion and a tube opening formed therein and eccentrically arranged relative to said axis.

9. As an article of manufacture, a forged steam boiler header having an elongated body portion and integral end walls, one of said end walls being of general convex form' and having a flattened portion extending at an oblique angle to and arranged mainly at `one side of the axis of said body portion and cut away to form a tube open-A 10. As an article of manufacture, a forged steam boiler header having an elongated body portion of substantially uniform circular crosssection and integral end walls, one of said end walls being of general convex form and having a flattened portion extending at an-oblique angle to andlarranged mainly at one side of the axis of said body portion and cut away to form a circular tube opening.

JOHN PRENTICE. 

